Understanding COVID-19 in TK-12 Schools in Los Angeles County

  • Vaccines offer effective protection against COVID-19. The case rate for unvaccinated individuals aged 12-18 years is almost 7 times higher than the case rate for vaccinated individuals of the same age group.
  • Testing volume is high. When open, schools are conducting over half a million tests each week to screen students and staff for COVID-19 to keep their campuses safe. With high levels of testing, the number of COVID-19 cases will increase but this does NOT reflect increased transmission if test positivity remains low.
  • Schools are safe. Evidence has shown that a multipronged prevention strategy that includes masking, physical distancing, testing, isolation of identified cases and quarantining of exposed individuals, and vaccination can help to reduce COVID-19 transmission on campus. (See COVID-19 Case Rates in TK-12 School and in the Community, Los Angeles County)
  • Data dashboards are transparent and actionable. The TK-12 School Data dashboard provides dynamic, visual information to learn about the status of COVID-19 in schools. This information can assist districts and schools to strengthen and target their COVID-19 prevention measures to ensure that schools remain a safe environment for students, teachers, and staff.

About the Data

  • Data reflect information reported to Public Health from TK-12 Schools and Youth Programs on COVID-19 cases among students, teachers, and staff.
  • Data may differ from information managed at the district- or school-level due to the reporting time period and data quality control conducted by Public Health staff.
  • Data are refreshed every Wednesday and reflect data from Monday to Sunday from the prior week. Due to updates and reporting delays, case counts may change in future reports.
  • If you have any questions, please contact acdc-education@ph.lacounty.gov.


School-based COVID-19 Testing

COVID-19 Weekly School Testing Volume and Test Positivity by Week, Los Angeles County Department of Public Health, Data between 02 Aug 2021 and 09 Jan 2022

  • For the weeks of 22 Nov 2021, 20 Dec 2021, and 27 Dec 2021, testing volume decrease was due to districts/schools being closed for holidays and delays in reporting.
  • Weekly data may include repeat tests for a unique individual.
  • School-based COVID-19 testing resources are supported via the American Rescue Plan Act of 2021 through the US Centers for Disease Control and Prevention Epidemiology and Laboratory Capacity for Prevention and Control of Emerging Infectious Diseases (ELC) Reopening Schools Award.
  • Test types reported by schools include PCR, rapid antigen, and over-the-counter tests.



COVID-19 School Testing Volume by School District or School, Los Angeles County Department of Public Health, Data between 03 Jan 2022 and 09 Jan 2022

  • Testing volume decrease is due to districts/schools being closed for the holiday break and delays in reporting over the break.
  • School-based COVID-19 testing resources are supported via the American Rescue Plan Act of 2021 through the US Centers for Disease Control and Prevention Epidemiology and Laboratory Capacity for Prevention and Control of Emerging Infectious Diseases (ELC) Reopening Schools Award. Public Health has partnered with the Los Angeles County Office of Education and Heluna Health to support COVID-19 testing in schools across the county.
  • Weekly data may include repeat tests for a single individual.
  • Missing values indicate that the district/school is in the planning phase of implementing their testing program under this award, or may be delayed in reporting their weekly data.
  • Number of staff and enrolled students is based on 2019-20 CALPADS student enrollment data and counts reported by the schools.
  • Test types reported by schools include PCR, rapid antigen, and over-the-counter tests.

COVID-19 Cases in TK-12 Schools

COVID-19 Cases in TK-12 Schools by Week, Data between 26 Oct 2020 and 09 Jan 2022

  • Case counts for the weeks of 22 Nov 2021 20 Dec 2021, and 27 Dec 2021 are lower than expected due to districts/schools being closed for the holiday breaks and delays in reporting.
  • For the 2020-2021 school year, TK-12 public and private schools were permitted to reopen for full in-person instruction beginning April 2021. Prior to that, in-person instruction was limited to certain specialized services, populations, and grade levels based on the COVID-19 risk-level tier as per the state’s “Blueprint for a Safer Economy.” For 2021-2022 school year, TK-12 public and private schools resumed full in-person instruction.
  • TK-12 schools are required to report all cases of laboratory-confirmed COVID-19 who were on campus within 14 days of their illness onset date to Public Health.
  • Cases are reported by earliest symptom onset date or positive COVID-19 test date (illness onset date). If both dates are missing, the first day of isolation or the date of case report is used.
  • Case counts include individuals who reside outside of Los Angeles County but attend, are employed by, or were visiting a school/program in Los Angeles County.
  • Instructional staff are defined as staff that are directly involved in school instruction such as teachers, while non-instructional staff include healthcare employees, public safety, administrators, and all other school support staff not directly involved in student instruction.
  • Data reported on COVID-19 cases may differ from the information managed at the district- or school-level due to the reporting time period and additional quality control conducted by Public Health staff.


COVID-19 Student Cases in TK-12 Schools by Week, Broken Down by School/Program Type, Data between 26 Oct 2020 and 09 Jan 2022

  • Case counts for the weeks of 22 Nov 2021, 20 Dec 2021, and 27 Dec 2021 are lower than expected due to districts/schools being closed for the holiday breaks and delays in reporting.
  • For the 2020-2021 school year, TK-12 public and private schools were permitted to reopen for full in-person instruction beginning April 2021. Prior to that, in-person instruction was limited to certain specialized services, populations, and grade levels based on the COVID-19 risk-level tier as per the state’s “Blueprint for a Safer Economy.” For 2021-2022 school year, TK-12 public and private schools resumed full in-person instruction.
  • TK-12 schools are required to report all cases of laboratory-confirmed COVID-19 who were on campus within 14 days of their illness onset date to Public Health.
  • Cases are reported by earliest symptom onset date or positive COVID-19 test date (illness onset date). If both dates are missing, the first day of isolation or the date of case report is used.
  • Case counts include individuals who reside outside of Los Angeles County but attend, are employed by, or were visiting a school/program in Los Angeles County.
  • Data reported on COVID-19 cases may differ from the information managed at the district- or school-level due to the reporting time period and additional quality control conducted by Public Health staff.


New COVID-19 Cases in the Past 7 Days by TK-12 Schools, Shown Both with COVID-19 Community Vaccination and Case Rates, Los Angeles County Department of Public Health, Data between 03 Jan 2022 and 09 Jan 2022

The maps below show new COVID-19 cases in the past 7 days by school. A school with one or more cases is not necessarily a school with ongoing transmission. Most identified cases are from community exposures unrelated to school.

  • Case counts for the week of 20 Dec 2021 are lower than expected due to districts/schools being closed for the holiday break and delays in reporting.
  • TK-12 schools are required to report all cases of laboratory-confirmed COVID-19 who were on campus within 14 days of their illness onset date to Public Health.
  • A school with one or more cases is not necessarily a school with ongoing transmission. As more schools continue to implement school-based COVID-19 testing, the weekly number of COVID-19 tests conducted will increase, leading to increased identification of COVID-19 cases by schools.
  • Schools with 3 or more new cases in the past 7 days do not reflect school outbreaks unless posted in the outbreak table below.
  • Case counts are reported by earliest symptom onset date or positive COVID-19 test date (illness onset date). If both dates are missing, the first day of isolation or the date of case report is used.
  • Case counts include individuals who reside outside of Los Angeles County but attend, are employed by, or visited a school/program in Los Angeles County.
  • Community COVID-19 case rates by school district are calculated as the 7-day average number of COVID-19 cases residing within a Los Angeles County school district boundary divided by the population residing within the school district boundary per 100,000 persons. Residence is based on reported home address.
  • Community vaccination by school district is calculated as the percentage of vaccine eligible children aged 5-11 years and 12-18 years who resided within a Los Angeles County school district boundary based on their reported home address, and received at least one dose of vaccine.
  • School districts with an indication of ‘Unreliable Data’ in vaccination rate include those with fewer than 5 people vaccinated or a potential error in the source data.
  • Data reported on COVID-19 cases may differ from the information managed at the district- or school-level due to the reporting time period and additional quality control conducted by Public Health staff.


Cumulative COVID-19 Cases in TK-12 Schools, Data between 16 Aug 2021 and 09 Jan 2022

  • The cumulative count of COVID-19 cases is calculated as the total number of laboratory-confirmed COVID-19 diagnoses reported by the school to Public Health from August 16, 2021 to date.
  • A school with one or more cases is not necessarily a school with ongoing transmission. Most identified cases are from community exposures unrelated to school. As more schools continue to implement school-based COVID-19 testing, the weekly number of COVID-19 tests conducted will increase, leading to increased identification of COVID-19 cases by schools.
  • Schools with 3 or more cases do not reflect school outbreaks unless posted in the outbreak table below.
  • Case counts are reported by earliest symptom onset date or positive COVID-19 test date (illness onset date). If both dates are missing, the first day of isolation or the date of case report is used.
  • Case counts include individuals who reside outside of Los Angeles County but attend, are employed by, or were visiting a school/program in Los Angeles County.
  • Data reported on COVID-19 cases may differ from the information managed at the district- or school-level due to the reporting time period and additional quality control conducted by Public Health staff.


COVID-19 Outbreaks in TK-12 Schools

A COVID-19 outbreak in TK-12 schools is opened when there are at least 3 or more laboratory-confirmed cases of COVID-19 within a 14-day period of each other in a specific group with members who are epidemiologically-linked, do not share a household, and are not a close contact of each other outside of the school. Out of over 3,000 schools in LA County, only a small fraction have COVID-19 outbreaks. Those that do are assisted by Public Health to mitigate spread.

Active COVID-19 Outbreaks in TK-12 Schools by Outbreak Site, Cases, and Contacts, Los Angeles County Department of Public Health, Data through 09 Jan 2022

Site Date Outbreak Opened Outbreak Type # Student Cases # Staff Cases # Student Close Contacts # Staff Close Contacts
Artesia High School 2021-12-29 Youth Sports 21 3 81 5
Bishop Amat Memorial High School, La Puente 2021-12-29 Youth Sports 39 6 87 12
Bishop Montgomery High School, Torrance 2021-12-30 Youth Sports 4 1 30 5
Bishop Mora Salesian High School 2021-12-28 Youth Sports 3 0 7 1
Calabasas High School 2021-12-23 Youth Sports 20 4 35 0
Canyon High School 2021-12-23 Youth Sports 21 3 20 2
Crossroads School for Arts and Sciences 2021-12-21 Youth Sports 12 2 16 1
Diamond Ranch High School 2021-12-27 Youth Sports 24 3 33 0
El Monte High School 2022-01-06 Youth Sports 5 0 0 0
El Segundo High School 2021-12-28 Youth Sports 13 1 5 0
Granada Hills Charter 2022-01-03 Youth Sports 4 1 0 0
La Serna High School 2021-12-27 Youth Sports 16 1 202 3
Loyola High School 2021-12-30 Youth Sports 7 1 7 1
Mark Keppel High School 2021-12-28 Youth Sports 19 2 21 2
Mira Costa High School 2021-12-17 Youth Sports 10 1 16 0
Mountain View High School 2022-01-04 Youth Sports 5 1 5 1
Notre Dame High School 2021-12-17 Youth Sports 48 3 369 0
Paraclete High School, Lancaster, Ca, 91709 2021-12-30 Youth Sports 16 4 6 2
Redondo Union High School 2021-12-29 Youth Sports 11 0 18 1
San Marino High School 2021-12-28 Youth Sports 8 1 10 4
Saugus High School 2021-12-29 Youth Sports 7 0 8 0
South Pasadena High School 2021-12-21 Youth Sports 18 1 7 0
The Buckley School 2021-12-28 Youth Sports 15 1 33 2
Trinity Classical Academy 2021-09-30 Classroom 7 1 100 0
Vasquez High School 2021-12-13 Classroom 11 0 123 0
Viewpoint School 2021-12-27 Youth Sports 9 6 9 5
Warren High School, Downey 2021-12-07 Youth Sports 6 2 110 1
Westside Neighborhood School, Los Angeles 2021-12-22 Youth Sports 1 3 46 4
Whittier High School 2021-12-23 Youth Sports 11 1 109 0
  • Epidemiologically-linked means that the cases were present at some point in the same setting during the same time while infectious.
  • Outbreaks that are active means that there has been at least one COVID-19 case that is epidemiologically-linked to the outbreak cluster within the past 14 days.